1. Field of the Invention
The present invention relates to support and/or comfort devices that include an inflatable bladder, and in particular to such devices that are adjustable and configurable.
2. Discussion of Related Art
One type of conventional inflatable device includes a plurality of seam-connected parallel tubes, each tube being an inflatable bladder, as illustrated in FIG. 1. This conventional inflatable device may be fabricated by sealing one layer of air-impervious film directly to another with a number of parallel seams 30, forming a plurality of parallel tubes 32. This type of structure, commonly used for inflatable rafts, is easily constructed and inexpensive, but has some limitations. In particular, this type of structure may often suffer from dimensional instability. As illustrated in FIG. 1, when inflated, the inflated tubes 32 are less wide than deflated tubes 34. Referring to FIGS. 2a and 2b, the conventional inflatable device is shown in a deflated condition. When empty of air the bladder is generally flat, having a length 36 and a width 38, as shown in FIGS. 2a and 2b. When inflated, the length and width of the bladder begin to shrink as the two layers of film separate. Referring to FIGS. 3a and 3b, it can be seen that the width 40 of the inflated bladder is significantly smaller than the width 38 of the empty bladder, while the change in length (36 to 41) of the bladder during inflation is negligible. Thus, the ratio of the length to the width of the device does not remain constant when the bladder is inflated. This dimensional instability of the conventional structures often limits the utility of the devices as cushions. The utility of the conventional structure as a cushioning surface is further limited by its irregular surface which provides uneven cushioning.